New spectrum of negative-parity doubly charmed baryons Mao-Jun Yan - PowerPoint PPT Presentation

New spectrum of negative-parity doubly charmed baryons Mao-Jun Yan Institute of Theoretical Physics, CAS School of Physics, BUAA Collaborators: Xiao-Hai Liu, Feng-Kun Guo, Sergi Gonzalez-Solis, C. Hanhart, U.-G. Meißner & B.S. Zou. 2019-08-20 Mao-Jun Yan New spectrum of negative-parity doubly charmed baryons 2019-08-20 1 / 20

Outline 4 2019-08-20 New spectrum of negative-parity doubly charmed baryons Mao-Jun Yan Backup slides 5 Summary 2 / 20 1 3 Heavy antiquark-diquark symmetry 2 Doubly charmed baryon in observation Doubly charmed baryon spectrum with J P = 1 − 2

cc and cc in c K c K Doubly charmed baryon in observation Lattice calculation: cc . S. Brown et al PRD90(2014) Observation of cc in mass spectrum LHCb, PRL119(2017) Mao-Jun Yan New spectrum of negative-parity doubly charmed baryons 2019-08-20 LHCb, JHEP1312(2013) cc , No signal Search for BaBar, PRD74(2006) annihilations , No signal in e e cc Search for SELEX, PLB628 (2005) SELEX, PRL89(2002) 3 / 20 First observation of Ξ + cc in Ξ + cc → Λ + c K − π + Confjrmation of Ξ + cc (3520) via its decay to pD + K −

c K Doubly charmed baryon in observation LHCb, JHEP1312(2013) 2019-08-20 New spectrum of negative-parity doubly charmed baryons Mao-Jun Yan LHCb, PRL119(2017) mass spectrum in cc Observation of S. Brown et al PRD90(2014) . cc Lattice calculation: 3 / 20 cc BaBar, PRD74(2006) SELEX, PRL89(2002) SELEX, PLB628 (2005) First observation of Ξ + cc in Ξ + cc → Λ + c K − π + Confjrmation of Ξ + cc (3520) via its decay to pD + K − Search for Ξ + cc and Ξ ++ in e + e − annihilations , No signal Search for Ξ + cc in Ξ + cc → Λ + c K − π + , No signal

c K Doubly charmed baryon in observation LHCb, JHEP1312(2013) 2019-08-20 New spectrum of negative-parity doubly charmed baryons Mao-Jun Yan LHCb, PRL119(2017) mass spectrum in cc Observation of S. Brown et al PRD90(2014) 3 / 20 BaBar, PRD74(2006) SELEX, PLB628 (2005) SELEX, PRL89(2002) cc First observation of Ξ + cc in Ξ + cc → Λ + c K − π + Confjrmation of Ξ + cc (3520) via its decay to pD + K − Search for Ξ + cc and Ξ ++ in e + e − annihilations , No signal Search for Ξ + cc in Ξ + cc → Λ + c K − π + , No signal Lattice calculation: Ξ cc (3610)(23)(22) .

Doubly charmed baryon in observation cc 2019-08-20 New spectrum of negative-parity doubly charmed baryons Mao-Jun Yan LHCb, PRL119(2017) S. Brown et al PRD90(2014) LHCb, JHEP1312(2013) BaBar, PRD74(2006) 3 / 20 SELEX, PRL89(2002) SELEX, PLB628 (2005) First observation of Ξ + cc in Ξ + cc → Λ + c K − π + Confjrmation of Ξ + cc (3520) via its decay to pD + K − Search for Ξ + cc and Ξ ++ in e + e − annihilations , No signal Search for Ξ + cc in Ξ + cc → Λ + c K − π + , No signal Lattice calculation: Ξ cc (3610)(23)(22) . Observation of Ξ ++ cc (3621) in Λ + c K − π + π + mass spectrum

Heavy anti-quark-diquark symmetry heavy quark is a static color (anti-)triplet in heavy meson. source,like a heavy anti-quark in heavy meson. It relates doubly-heavy baryons to anti-heavy mesons. Mao-Jun Yan New spectrum of negative-parity doubly charmed baryons 2019-08-20 4 / 20 m Q v ≫ Λ QCD , heavy diquark serves as a point-like color anti-triplet

5 / 20 with mass m 2019-08-20 New spectrum of negative-parity doubly charmed baryons Mao-Jun Yan Does inner structure of heavy diquark contribute to spectrum? F.-K. Guo and U.-G. Meißner PRD84(2011); Zhi-Hui Guo, PRD96 (2017) doubly charmed baryons. While SU(3) multiplet calculated for GBs scattering ofg ground states of GeV . m D m D s cc cc Prediction: Extended to doubly charmed baryon, PRD76(2007) ;F.K. Guo et al PLB(641)(2006), EPJ.A40(2009), PR D87 (2013); L.S. Geng et al PRD89(2014); T. Barnes et al PRD68(2003); E.E. Kolomeitsev et al PLB582(2004) ; A. Faessler et al PRD76(2007); D. Gamermann et al charmed mesons and doubly charmed baryons. Following heavy anti-quark-diquark symmetry, there is a bridge between Doubly charmed baryon with J P = 1 − 2 D ∗ s 0 (2317) D ∗ s 0 (2317) is understood as DK bound state mainly.

5 / 20 PRD76(2007) ;F.K. Guo et al PLB(641)(2006), EPJ.A40(2009), PR D87 (2013); L.S. Geng et al PRD89(2014); 2019-08-20 New spectrum of negative-parity doubly charmed baryons Mao-Jun Yan Does inner structure of heavy diquark contribute to spectrum? F.-K. Guo and U.-G. Meißner PRD84(2011); Zhi-Hui Guo, PRD96 (2017) doubly charmed baryons. While SU(3) multiplet calculated for GBs scattering ofg ground states of Extended to doubly charmed baryon, charmed mesons and doubly charmed baryons. T. Barnes et al PRD68(2003); E.E. Kolomeitsev et al PLB582(2004) ; A. Faessler et al PRD76(2007); D. Gamermann et al Following heavy anti-quark-diquark symmetry, there is a bridge between Doubly charmed baryon with J P = 1 − 2 D ∗ s 0 (2317) D ∗ s 0 (2317) is understood as DK bound state mainly. Prediction: Ω cc (1/2 − ) with mass m Ξ cc + m D ∗ s 0 (2317) − m D ≈ 4 . 1 GeV .

5 / 20 PRD76(2007) ;F.K. Guo et al PLB(641)(2006), EPJ.A40(2009), PR D87 (2013); L.S. Geng et al PRD89(2014); 2019-08-20 New spectrum of negative-parity doubly charmed baryons Mao-Jun Yan Does inner structure of heavy diquark contribute to spectrum? F.-K. Guo and U.-G. Meißner PRD84(2011); Zhi-Hui Guo, PRD96 (2017) doubly charmed baryons. While SU(3) multiplet calculated for GBs scattering ofg ground states of Extended to doubly charmed baryon, charmed mesons and doubly charmed baryons. T. Barnes et al PRD68(2003); E.E. Kolomeitsev et al PLB582(2004) ; A. Faessler et al PRD76(2007); D. Gamermann et al Following heavy anti-quark-diquark symmetry, there is a bridge between Doubly charmed baryon with J P = 1 − 2 D ∗ s 0 (2317) D ∗ s 0 (2317) is understood as DK bound state mainly. Prediction: Ω cc (1/2 − ) with mass m Ξ cc + m D ∗ s 0 (2317) − m D ≈ 4 . 1 GeV .

6 / 20 PRD73,054003(2006) 2019-08-20 New spectrum of negative-parity doubly charmed baryons Mao-Jun Yan L QQ , Spin structure in heavy diquark r d Size of doubly charmed baryon Doubly charmed baryon with J P = 1 − 2 r d ≈ 1/( m Q v Q ) ≈ 0 . 25 fm with m Q v Q ≈ 800 MeV r q ≈ 1/Λ QCD ≈ 0 . 8 fm with Λ QCD ≈ 250 MeV . r q ≈ 0 . 3 Value of m Q v Q is given in J. Hu and T. Mehen J QQ = ⃗ ⃗ S QQ + ⃗ S QQ = 1 , L QQ = 0 in ground state, P (+) S QQ = 0 , L QQ = 1 in P-wave excitation. P ( − )

QCD m c 7 / 20 cc in S-wave P P cc u This term breaks HQSS and h c couples to is expected to be T. Mehen et al PRD73,054003(2006), PRD96,094028(2017) Mao-Jun Yan New spectrum of negative-parity doubly charmed baryons 2019-08-20 cc cc T.Mehen PRD96 (2017) P consideration? 2. How to take these P-wave excitations in heavy diquark into and u- channel) should be a degree of freedom in spectrum of doubly charmed baryon. (s- Potential of P-wave excitation in heavy diquark: Something new? Doubly charmed baryon with J P = 1 − 2 V P ( cc ) = 1 2 V P ( c ¯ c ) is predicted in quark model. cc − M ψ cc ≈ ( M h c − M J / ψ )/2 = 214 MeV . M ψ P 1. 214 MeV = O ( m π , m K , m η ) , P-wave excitation in heavy diquark

7 / 20 Something new? 2019-08-20 New spectrum of negative-parity doubly charmed baryons Mao-Jun Yan consideration? and u- channel) should be a degree of freedom in spectrum of doubly charmed baryon. (s- 2. How to take these P-wave excitations in heavy diquark into T.Mehen PRD96 (2017) Potential of P-wave excitation in heavy diquark: Doubly charmed baryon with J P = 1 − 2 V P ( cc ) = 1 2 V P ( c ¯ c ) is predicted in quark model. cc − M ψ cc ≈ ( M h c − M J / ψ )/2 = 214 MeV . M ψ P 1. 214 MeV = O ( m π , m K , m η ) , P-wave excitation in heavy diquark − ) couples to ψ cc φ in S-wave cc ( 1 ψ P 2 L P = λ ¯ cc γ µ u µ ψ cc + h . c . ψ P This term breaks HQSS and λ is expected to be O (Λ QCD / m c ) = O (0 . 2) ≪ 1 T. Mehen et al PRD73,054003(2006), PRD96,094028(2017)

8 / 20 cc 2019-08-20 New spectrum of negative-parity doubly charmed baryons Mao-Jun Yan u-channel Born terms is small. Born terms in s-channels are considered and the contribution from Doubly charmed baryon with J P = 1 − 2 V s = 2 λ 2 1 F 2 C ( s ) ¯ u f ( p 3 , σ f )/ p 2 u i ( p 1 , σ i ) , / p 4 P − ˚ / M ψ P √  3 1 6  ( − 2 ) 2 2 2 2 √ 1 1 1 3 √ ,   2 6 − 2 2 6 √ √   3 3 6 1 I =0 1 √ 2 6 I =1/2 I = 0 : Ξ cc ¯ K − Ω cc η ; I = 1/2 : Ξ cc π − Ξ cc η − Ω cc K

9 / 20 with 2019-08-20 The interactions in LO ChPT contain Weinberg-Tomozawa terms and Born terms with ground state of doubly charmed baryons exchanging. New spectrum of negative-parity doubly charmed baryons Mao-Jun Yan Doubly charmed baryon with J P = 1 − 2 L LO = ¯ 2 γ µ γ 5 u µ ) ψ cc . ψ cc ( i / D − m 0 + g A D µ = ∂ µ + 1 [ u † ∂ µ u + u ∂ µ u † ] , u µ = iu † D µ Uu † 2 The axial coupling constant g A is estimated as, | g A | = 0 . 2

10 / 20 cc 2019-08-20 The ground-state doubly charmed baryons are expected to form a fmavor triplet of matter fjelds, New spectrum of negative-parity doubly charmed baryons Mao-Jun Yan with F cc . cc Doubly charmed baryon with J P = 1 − 2 Ξ ++   Ξ + ψ cc =   Ω + The light pseudoscalar mesons ( π, K , η ) are the Goldstone bosons of QCD, √ U = u 2 = e i 2Φ 2 π 0 + 1 1 π + K +   6 η √ √ 2 π 0 + − 1 1 K 0 π − 6 η Φ = √ √     ¯ K − K 0 − 2 6 η √